What does it mean when you smell burning rubber but nothing is burning?

Ever smelled smoke, burnt toast, or sewage when there was no such scent around? You could be one of millions who experience phantom smells, or phantosmia, as it’s known in the medical community (more on that in the sidebar “What is Phantosmia?”).

According to a study published in JAMA Otolaryngology-Head and Neck Surgery, one in 15 Americans smells a phantom smell. Most often, these phantom smells are unpleasant (e.g., burning hair, sewage, or cigarette smoke). Sometimes they’re an indication that something more serious is going on—like a brain tumor or an epileptic seizure. The good news: Phantosmia often decreases with age, especially in women.

So, what are phantom smells? “A phantom odor is when someone perceives an odor but there is nothing in the environment that corresponds to the odor,” explains Kathleen Bainbridge, PhD, an epidemiologist in the Epidemiology and Statistics Program at the National Institutes of Health.

These phantom smells are commonly perceived as negative. The adjectives used to describe the most prevalent scents include smoky, burnt, unpleasant, spoiled, or rotten, according to Swedish researchers. Metallic smells, cooked food, and dusty or dirty odors were also noted.

On a positive note, some phantosmic people experience their phantom smell as neutral or positive (e.g., perfume or a flower). According to the study, these smells appear fleetingly, most commonly lasting for a few minutes.

WHAT IS PHANTOSMIA?

The medical term used to describe phantom smells is phantosmia, a disorder also known as an olfactory hallucination. Those who suffer from phantosmia experience imaginary odors. Some smell the odor in one nostril while others catch a whiff through both.

For certain people with phantosmia, the phantom smell may be chronic while others say it comes and goes. Causes include a head injury, brain tumor, Parkinson’s disease, upper respiratory infection, and inflamed sinuses.

What Causes Phantom Smells?

Ever wondered, “Why do I smell something that is not there?” Turns out a bunch of factors may be at play.

“The causes of phantom odor perception are not understood,” Dr. Bainbridge says. “The condition could be related to overactive odor sensing nerve cells in the nasal cavity or perhaps a malfunction in the part of the brain that understands odor signals.”

Some of the most common causes of phantom smells may include:

• Age (those over 40 are more likely to experience phantom smells)
• Abscess
• Brain tumor
• Chronic dry mouth
• Dysfunction at the olfactory nerve
• Epilepsy
• Genes (Swedish researchers have found a link between the BDNF met allele and phantosmia)
• Head injury
• Inflamed sinuses
• Medications (especially those that cause dry mouth)
• Migraine
• Parkinson’s disease
• Parosmia (a condition that involves a distorted sense of smell – smelling odors that are different than the scent involved)
• Poor overall health
• Sinusitis
• Temporal lobe seizure
• Tumors
• Upper respiratory infection

Those who are of a low socio-economic status are more likely to experience phantom smells. The reason? “People with lower socio-economic status may have health conditions that contribute to phantom odors, either directly or because of medications needed to treat their health conditions,” Dr. Bainbridge explains.

Phantom Smells Are a Symptom of…

Since our sense of taste is directly tied to our sense of smell, phantosmia can cause frustrating effects. But, Dr. Bainbridge reassures, “Phantom odors are not known to be a sign of serious underlying illness.”

As for their negative qualities, phantom smells can have an impact a person’s internal warning system. Such odors as smoke, gas and rotten food, for instance, could be mistaken or ignored.

THE “UNCLE” HALLUCINATION

The phantom smell you experience could tell you something about your health, says Alan Hirsch, MD, of the Smell & Taste Treatment and Research Foundation. Those who smell burning rubber, or smoke, for instance may be suffering from an “uncle hallucination” associated with temporal lobe epilepsy. “These uncle hallucinations are the equivalent of seeing light in migraine, but instead, [people] can smell smells,” he says.

Phantom smells also can lead to a decrease in appetite, they can turn someone off certain foods, and they may prevent the enjoyment of things (e.g., ice cream) that someone once favored. As such, phantom smells can actually result in depression, negative mood, and difficulties socializing.

Furthermore, Alan Hirsch, MD, Neurological Director of the Smell & Taste Treatment and Research Foundation, believes “phantom smells may indicate a medical or psychological condition.”

A few psychological illnesses that could cause phantom smells include:

• Delusional disorder
• Cotard’s syndrome
• Schizophrenia?
• Olfactory reference syndrome

Are Phantom Smells Common?

Quite. In her study of 7,417 U.S. adults over the age of 40, some 6.5 percent experienced phantom odors, Dr. Bainbridge found. “We found a higher prevalence in 40- to 60-year-olds compared to 60-plus-year-olds,” says Bainbridge. Her study also found that women are more likely to experience phantom smells than men.

The good news: Phantom smells seem to decrease with age.

How to Get Rid of Phantom Smells

Unfortunately, there is a lack of consensus on this important topic. That could be part of the reason why only 11 percent of those who suffer phantom smells seek professional help.

According to Hirsch, the first step to treating phantom smells is diagnosing their cause. Once you’ve determined why you’re smelling something that isn’t there, he says, you can try to treat it. “If it’s temporal lobe epilepsy, then you treat it with anticonvulsants,” Hirsch explains. “If it’s a tumor, then you cut the tumor out. If it’s sinusitis, you treat it with antibiotics.”

In some cases, the phantom smell is idiopathic, meaning it has no known cause. Essentially the brain is misinterpreting sensory stimuli. “The air is coming in through the nose and it’s being processed as a smell,” Hirsch explains. To combat this, some doctors treat patients with anticonvulsants. Here’s how they work: First, the brain views the air as a smell. Then, the anticonvulsant destabilizes “the nerve membrane [so] the nerves don’t fire off and the smell goes away.”

Other times, phantom smells result from smell loss. “When you lose your sense of smell, sometimes a phantom smell will appear and replace the smell that you no longer have,” Hirsch explains. The solution: to treat the underlying condition (i.e. smell loss) to improve phantosmia.

That said, Bainbridge claims “there are no reliable treatments for people who find phantom odors to be bothersome. Sometimes medications are tried. Sometimes, people have to cope with the symptoms until they subside.”  Confused yet?

Note: See a doctor if you’re constantly noticing a phantom smell, or if you notice a loss of smell. He or she may conduct various tests to determine the cause of your condition. Once phantom smells occur, “it may be nothing, or it may indicate an underlying disease that needs treatment,” Hirsch says.

How to Tell Whether You’re Experiencing Phantom Smells

It’s tough to know whether you’re smelling something that others aren’t. Next time you smell something strange, ask someone nearby if he or she smells the same thing.

Another test: Hold your nose and your breath to see if the smell disappears. Then, try Hirsch’s ice cream test to establish whether you’re struggling with reduced smell. Here’s how:

Step 1: Get two bowls of ice cream: one of vanilla and the other chocolate
Step 2: Taste the vanilla ice cream
Step 3: Taste the chocolate ice cream
Step 4: Determine whether you can taste a difference between the two.

“More than 90 percent of taste is smell, so almost all of chocolate is the smell, not the taste of it,” Hirsch says. “If you lose your sense of smell, it tastes the same as vanilla ice cream. So, if you can’t tell the difference between those two, that may indicate that you’ve had a a smell loss.”

Danny Lipford contributed to this article, which originally appeared on Bottom Line Inc.

You think you smell fish – even though you haven’t cooked anything resembling salmon or swordfish in days. Or maybe it’s the smell of your fireplace – even though you haven’t set fire to a log in weeks. Or the odor resembles ammonia, rotten eggs or something else entirely.

Such household odors can serve as clues that there are hidden dangers in the home – problems that could be pricier to repair and potentially hazardous to your health if not found and fixed fast.

1. Fishy Smell That’s Not Fish

   Some people refer to this as a urine or burning rubber smell. This could be something electrical in the home overheating and melting its insulating plastic or ­rubber—which could lead to a fire.

   The most likely culprit is an appliance, such as a dishwasher, washing machine or an air conditioner. Sniff near each of these while they are running to try to identify the source. When you think you have found the source, either call in a repair professional to investigate… or replace the appliance if it is approaching the end of its useful life.

   Warning: If the odor seems to be emanating from a wall switch, outlet or some other part of your home’s electrical wiring, not an appliance, switch off the circuit breaker and call an ­electrician.

2. Ammonia Smell That’s Not Ammonia

   Some people describe this as the smell of death, and they’re right—a mouse or some other small animal likely has died inside your home. One solution is to find and remove the corpse, and that’s often easier said than done—there’s a good chance that it is in a hard-to-reach spot inside your walls, ceiling or floor.

   Use your nose to find where the smell is strongest, and search everywhere you can in that area. Consider buying and using a small snaking digital inspection camera to peek into walls, behind cabinets and appliances and into other tight spots. Ridgid Hand-Held inspection cameras are a good choice, starting at less than $150.

   Unfortunately, even with a snaking camera, you won’t be able to see everywhere without drilling holes in walls, and that usually causes more problems than it solves. Of course, you could just wait for the smell to go away, which typically takes a few weeks.

   Meanwhile, inspect the perimeter of your home for gaps where rodents can enter, and seal these to prevent further invasions. Also, deploy rodent traps—not rodent poison—in the home. If you use poison, additional rodents might die in their hard-to-reach nests inside your home, creating more bad smell.

3. Damp, Musty Smell

   This usually signals mold or mildew, which could become a big problem for both your home and your health if not quickly remedied. Use a digital ­hygrometer to check the relative humidity of each room in the house—you can find these for less than $10 online or at home-improvement stores. If you get readings above 50%, run a dehumidifier. Apply an antimicrobial spray to carpets, curtains and fabric-covered furniture in any room that has high humidity and/or a musty odor.

   Meanwhile, search these rooms for water leaks. Look behind refrigerators and under sinks for wet spots. Visit the room during the next hard rain to look for visible leaks. Go down to the basement, crawl space or room directly beneath this musty room to look for evidence of water leaks there, too—those could point to leaks that are hard to spot in the room above.

4. Musty/Smoky Odor From a Fireplace That’s Not In Use

   First, make sure that the chimney dampers are closed. Chimney smells can be drawn into the house when these are left open.

   

   If that’s not the problem, vacuum and then scrub the “firebox”—the area that contains the fire at the base of the chimney. If the smell persists after the firebox has dried following this cleaning, call in a chimney sweep to clean and inspect your chimney. Mention that you suspect water might be getting in. The problem might be as simple as a dislodged chimney cap, or there might be cracks in the masonry.

   Make sure the chimney sweep checks whether the damper is sealing ­sufficiently. You can purchase and use an inflatable damper, sometimes called a fireplace draft stopper. These are available for less than $100.

   Dusty burning smell when you turn on your heat for the first time in months. Burning smells understandably trigger home owner anxieties, but this one usually is not a problem—the dust that settled on the unit over the summer is simply burning away. This smell should disappear on its own within a few hours of turning on the heat. Do replace your HVAC system’s filter if you haven’t done so recently because it might be allowing excessive dust to collect on heating components.

   Warning: Turn off your heating system, and call in an HVAC repair pro if you see smoke coming from vents and/or the burning smell occurs at any time other than the heating system’s first few uses of the season.

5. Chemical Smell From New Furniture, Carpet or Paint

   A fresh coat of paint, a new piece of pressed-board furniture or a new carpet can off-gas volatile organic compounds (VOCs) that are not just unpleasant to smell but also unhealthy to breathe. When possible, remove new pressed-wood furniture and carpeting from its packaging and let it air out in your garage for at least an hour, and preferably overnight, before bringing it into your home. If that isn’t feasible, open all the windows in the room and run fans to circulate the air for at least an hour and as long as a full day. That method also works when you are painting interior walls.

6. Sewage Smell

   This sometimes is confused with the rotten-egg smell, but it’s less “eggy” and more like the smell of an outhouse or a portable toilet. It probably is coming from a drain. Use your nose to determine which one—it could be the drain of a toilet, sink, tub or shower.

   

   One possibility is that there isn’t enough water in this drain’s “P trap.” The P trap is a curved piece of pipe below the drain that should be full of water—the water blocks offensive odors from your sewer line or septic tank from wafting back into the house. If this is the case, running the water for a few seconds (or flushing the toilet) should solve the problem. You also will have to air out the house to get rid of the odor that’s already there. This is especially likely if the toilet, sink, tub or shower has gone unused for months—the water in the P trap might have evaporated.

   If that does not solve the problem—or if you see that the water is not draining properly—the odor probably is coming from material clogged in the drain line. Put on rubber gloves, and use a flexible 16-to-18-inch drain-cleaning brush to clear out any gunk from the drain. Next, let the hot water run for a few minutes (or flush the toilet) to confirm that it is now draining properly. Then shut off the water and pour one cup of bleach into the drain. Let the bleach sit for 30 to 60 minutes, then run the hot water (or flush the toilet) again. If the odor persists, you may need to rent or purchase a plumber’s auger or snake to dislodge the clog.

7. Rotten-Egg Smell Could Be Two Things

   A rotten-egg smell might be a potentially dangerous natural gas leak. Get everyone out of the house—leaving the door and windows open so that some gas can escape—and call your gas company immediately to report the problem and request further instructions. Natural gas itself is odorless, but a sulfur-like rotten-egg smell is added so that leaks will be detected.

8. If a faint rotten-egg smell occurs only when your hot water is running, however, it’s probably not a gas leak at all but rather a small amount of odorous sulfur in the water. Sometimes you or a plumber can solve this problem by shutting off the water line leading to the water heater, using a hose to drain the tank, then refilling the tank.